As a teaser, here is an introduction to Qaiku Data:
Inspired by the Twitter Data initiative, Qaiku is starting to support machine-readable metadata in Qaiku messages. Unlike Twitter Data, Qaiku Data is stored as its own field alongside the message, in order not to clutter the actual message displayed on website and in Qaiku clients.
Qaiku Data is handled as key-value pairs marked by $key value. Multiple keys and values can be supplied by separating them with space, like in $key1 value1 $key2 value2.
In Qaiku JSON feeds, data is shown in the data field of the message. On website, they're shown in a qaiku:data attribute of the message <div />.
Qaiku data is limited to 256 characters per message.